Non-SMT equipment used in LED lighting manufacture covers a vast range of options. This article guides readers through the complex decision-making process
By Sneha Ambastha
Different types of LED lighting products are available in the market today in various shapes and sizes. But what most people are not aware of is that technically, there are only two types of LED based products.
One based on through-hole technology, which involves a slow manual manufacturing process, and the other based on surface mount technology, which uses fast, automated manufacturing lines.
Thus, the manufacturing tools and equipment used in both the processes are entirely different. In this issue, we bring readers the essential information required to purchase manufacturing equipment for through-hole based LED lighting products.
The equipment involved
Any LED light is a combination of a light emitting diode (LED), an LED lens, a heat sink, LED driver, the light housing and fittings. The entire process is referred to as light packaging. But, before the packaging of an LED light, a PCB assembly is required.
The PCB assembly process requires soldering/desoldering machines and rework stations/machines whereas the light assembly or packaging process requires non-SMT assembly lines. The entire process involves a lot of manpower and time.
Although there are plenty of small tools such as tweezers, soldering irons, fluxes, etc, used in the course of the complete manufacturing process, it is important to be clear about the big equipment required.
Soldering stations: These are electronic circuits with a soldering iron, temperature sensor, power supply, a temperature display and controller to set the heat limit of the iron. Nowadays, soldering stations come with more channels in order to plug more than one soldering iron. They are used to solder the components on the printed circuit board.
Desoldering stations: These are a combination of a solder wick, hot air gun, desoldering pump and removal alloys used to remove the components and the solder from the PCB.
Rework stations: These are a combination of soldering and desoldering tools. They are used to repair and refine the PCB assembly process. They are usually used to solder and desolder the surface mounted components.
Selective soldering machines: These are soldering systems used to solder only selected components that would otherwise get damaged in the SMT soldering process.
Component forming machines: These equipment are used to cut, bend and adjust the metal piece of the through-hole components (ideally, in the radial or axial pattern) to make their placement on the PCB easy. This is a useful tool to form components required in bulk manufacturing. These are also termed as lead formers or benders.
Dip soldering machines: These are special types of soldering machines with a molten solder bath in which the PCBs with the components are placed, in order to expose the metal areas on the PCB directly to the wet solder, to build reliable electrical connections.
Wire bonders: These are the machines used to make connections between semiconductor devices and their packaging.
Curing machines: Curing is the process of drying the adhesives or the coating done on the PCB and the components placed upon it. The machines used for this process are called curing machines.
Drilling machines: These machines are used for various drilling jobs on the PCB and on other parts to make better connections.
Screen printing machines: Manual or semi-automatic screen printing machines are used for printing the solder paste on the PCB during the manufacturing process. Although semi-automatic printers involve both manual and automatic processes with less errors, manual printing is 100 per cent operator dependent with the maximum probability for errors.
Then there are manual or semi-automatic light assembly machines.
Selection is never easy
The continual development of science and technology has today left us with plenty of options with respect to the equipment discussed here. But before making these important investments, it is advisable to do a little homework for a better output.
Understand the component characteristics: If we take the example of a small LED bulb, it has plenty of components in it and each one has its own characteristics with regard to the stress handling capacity, ESD characteristics, temperature limits, etc.
Now, if you use a curing machine with a high temperature, which is not suitable for any one of the components used while making this bulb, the component could get damaged and have to be replaced. During bulk manufacturing, such mistakes cannot be made as it would result in wastage of high volumes.
Another important reason for being better informed is that different types of LED packages require different types of customisation in the equipment used.
Focus on low cost equipment with better output: Big assembly lines for LED lights are quite expensive owing to their size and the functionality they provide. Moreover, it is not just a one-time investment with these equipment; there are a lot of recurring maintenance costs involved.
Again, if you do not want to keep your customers waiting when the equipment breaks down, then you will have to get at least two identical types of machines for the same work, which means extra investments.
A manual or a semi-automatic assembly line can help one save a lot of money in such situations as they are available at much cheaper rates.
Check after-sales service support: Regular use of any manufacturing equipment can result in a lot of wear and tear, especially when these are used for bulk production. In such situations, these machines require a lot of after-sales service support, which ideally, should be provided by the manufacturing firm or its local distributor.
One can go for self servicing of these machines only if there are proper guidelines laid out. Big vendors usually provide better services with developed guidelines to make the work easier for their customers.
High precision equipment: With the growth of the LED lighting industry, the demand for LED lights in various shapes and sizes has increased, leading to the requirement of high precision, efficient manufacturing tools and equipment.
If the selection proves to be wrong, the final product manufactured will not be of the quality acceptable by the end customers.
Apart from the points discussed above, there are certain key specifications that are to be checked based on the functionality of the equipment selected and the type of the components used.
